GtkOffscreenWindow

GtkOffscreenWindow — A toplevel container widget used to manage offscreen rendering of child widgets.

Synopsis

#include <gtk/gtk.h>

                    GtkOffscreenWindow;
GtkWidget *         gtk_offscreen_window_new            (void);
GdkPixmap *         gtk_offscreen_window_get_pixmap     (GtkOffscreenWindow *offscreen);
GdkPixbuf *         gtk_offscreen_window_get_pixbuf     (GtkOffscreenWindow *offscreen);

Object Hierarchy

  GObject
   +----GInitiallyUnowned
         +----GtkObject
               +----GtkWidget
                     +----GtkContainer
                           +----GtkBin
                                 +----GtkWindow
                                       +----GtkOffscreenWindow

Implemented Interfaces

GtkOffscreenWindow implements AtkImplementorIface and GtkBuildable.

Description

GtkOffscreenWindow is strictly intended to be used for obtaining snapshots of widgets that are not part of a normal widget hierarchy. It differs from gtk_widget_get_snapshot() in that the widget you want to get a snapshot of need not be displayed on the user's screen as a part of a widget hierarchy. However, since GtkOffscreenWindow is a toplevel widget you cannot obtain snapshots of a full window with it since you cannot pack a toplevel widget in another toplevel.

The idea is to take a widget and manually set the state of it, add it to a GtkOffscreenWindow and then retrieve the snapshot as a GdkPixmap or GdkPixbuf.

GtkOffscreenWindow derives from GtkWindow only as an implementation detail. Applications should not use any API specific to GtkWindow to operate on this object. It should be treated as a GtkBin that has no parent widget.

When contained offscreen widgets are redrawn, GtkOffscreenWindow will emit a "damage-event" signal.

Details

GtkOffscreenWindow

typedef struct _GtkOffscreenWindow GtkOffscreenWindow;


gtk_offscreen_window_new ()

GtkWidget *         gtk_offscreen_window_new            (void);

Creates a toplevel container widget that is used to retrieve snapshots of widgets without showing them on the screen. For widgets that are on the screen and part of a normal widget hierarchy, gtk_widget_get_snapshot() can be used instead.

Returns :

A pointer to a GtkWidget

Since 2.20


gtk_offscreen_window_get_pixmap ()

GdkPixmap *         gtk_offscreen_window_get_pixmap     (GtkOffscreenWindow *offscreen);

Retrieves a snapshot of the contained widget in the form of a GdkPixmap. If you need to keep this around over window resizes then you should add a reference to it.

offscreen :

the GtkOffscreenWindow contained widget.

Returns :

A GdkPixmap pointer to the offscreen pixmap, or NULL.

Since 2.20


gtk_offscreen_window_get_pixbuf ()

GdkPixbuf *         gtk_offscreen_window_get_pixbuf     (GtkOffscreenWindow *offscreen);

Retrieves a snapshot of the contained widget in the form of a GdkPixbuf. This is a new pixbuf with a reference count of 1, and the application should unreference it once it is no longer needed.

offscreen :

the GtkOffscreenWindow contained widget.

Returns :

A GdkPixbuf pointer, or NULL.

Since 2.20